Thread: Memory allocation for postmaster service...
I’m just wondering if it’s possible to increase the allocation of memory to the postmaster service. I’m running PosgreSQL with PostGIS, and sometimes running a map query on multiple objects from Mapserver can take a very long time with the CPU running at 100%. I’m hoping increasing the memory allocation would improve the performance...
Kind regards,
Mike
Memory allocation could be the issue, but first try looking at your indexes. That almost always solves any speed issues for me. If you haven't yet, try EXPLAIN ANALYZE.
Kevin
----- Original Message -----From: Mike LeahySent: Wednesday, September 17, 2003 1:44 PMSubject: [CYGWIN] Memory allocation for postmaster service...Im just wondering if its possible to increase the allocation of memory to the postmaster service. Im running PosgreSQL with PostGIS, and sometimes running a map query on multiple objects from Mapserver can take a very long time with the CPU running at 100%. Im hoping increasing the memory allocation would improve the performance...
Kind regards,
Mike
Sometimes if you put a column in the WHERE part of the query that is in one of the indexes, even you aren't using it, sometimes that will force use of an index. Or what you can try is if you have multiple parts in your WHERE statement (e.g where column1 = 1 and column2 = 2) try creating an index that has both of those in there. There are a number of different things like that which you can use to trick PostgreSQL into using an index. I've had the same problems where PostgreSQL won't use an index but the methods I've stated above have worked for me in the past. Kevin ----- Original Message ----- From: Mike Leahy To: 'Kevin Schroeder' Sent: Wednesday, September 17, 2003 4:56 PM Subject: RE: [CYGWIN] Memory allocation for postmaster service... I've got spatial indexes for the spatial tables, as well as relevant standard indexes on other tables (but which I'm not using in this specific case). It helped a little, but not much. The EXPLAIN ANALYZE never revealed much to me...in fact, the queries almost never choose to use the indexes over a straight sequential search...as far as I know, there's no way to force it to use the indexes. Mike -----Original Message----- From: pgsql-cygwin-owner@postgresql.org [mailto:pgsql-cygwin-owner@postgresql.org] On Behalf Of Kevin Schroeder Sent: September 17, 2003 2:49 PM To: pgsql-cygwin@postgresql.org Subject: Re: [CYGWIN] Memory allocation for postmaster service... Memory allocation could be the issue, but first try looking at your indexes. That almost always solves any speed issues for me. If you haven't yet, try EXPLAIN ANALYZE. Kevin ----- Original Message ----- From: Mike Leahy To: pgsql-cygwin@postgresql.org Sent: Wednesday, September 17, 2003 1:44 PM Subject: [CYGWIN] Memory allocation for postmaster service... I'm just wondering if it's possible to increase the allocation of memory to the postmaster service. I'm running PosgreSQL with PostGIS, and sometimes running a map query on multiple objects from Mapserver can take a very long time with the CPU running at 100%. I'm hoping increasing the memory allocation would improve the performance... Kind regards, Mike